However, Key today insisted there was a difference between "raw intelligence", which was what Dotcom wanted, and files created by the spy agency.

The law required that the former be deleted (or "aged off") once it was no longer relevant. Dotcom was "quite wrong", he said.

"There aren't files missing," Key said.

"As I understand it, there is raw material that ages off the system and Section 23 of the [GCSB] act demands that ... data that is collected, that's intelligence, over time, if that is no longer relevant then it falls off the system."

Opponents of beefed-up spying powers, introduced last year, had argued that the GCSB should not hold onto to information, he said.